A green tire building apparatus comprising bead lock segments arranged in the circumferential direction of a building drum at bead-set positions disposed at the both sides of a main body of building drum and movable in the radial direction of the building drum; a turn-up bladder disposed in a state of extending up to a posiition axially outer than the opposite ends of the main body of building drum through the outer sides of a row of these bead lock segments in the axial direction thereof; an elastic ring-shaped member disposed on the outer peripheral portion of the bead lock segments; a member movable in the axial direction of the building drum; a driving means for driving this movable member; and a driving converting mechanism for converting the movement of the movable member to the movement of the respective bead lock segments in the radial direction of the drum. Further, a green tire building apparatus comprising bead lock segments provided at bead-set positions on both sides of a main body of building drum, having on the outer peripheral portion thereof grooves opening outwardly, which grooves being arranged in the circumferential direction of the building drum in such a manner that these grooves are connected to one another to form a ring-shaped groove, and movable in the diametrical direction of the building drum; an elastic ring-shaped member housed in the ring-shaped groove of these bead lock segments; and a turn-up bladder formed separately from this elastic ring-shaped member and disposed in such a state as to extend up to a position axially outer than the opposite ends of the building drum through the outer sides of this elastic ring-shaped member in the radial direction thereof. <IMAGE>
